Bacterial Microbiome in the Phyllo-Endosphere of Highly Specialized Rock Spleenwort.

Bacteria communities associated with plants have been given increasing consideration because they are arguably beneficial to their host plants. To understand the ecological and evolutionary impact of these mutualistic associations, it is important to explore the vast unknown territory of bacterial genomic diversity and their functional contributions associated with the major branches of the tree-of-life. Arguably, this aim can be achieved by profiling bacterial communities by applying high throughput sequencing approaches, besides establishing model plant organisms to test key predictions. This study utilized the Illumina Miseq reads of bacterial 16S rRNA sequences to determine the bacterial diversity associated with the endosphere of the leaves of the highly specialized rock spleenwort Asplenium delavayi (Aspleniaceae). By documenting the bacterial communities associated with ferns collected in natural occurrence and cultivation, this study discovered the most species-rich bacterial communities associated with terrestrial ferns reported until now. Despite the substantial variations of species diversity and composition among accessions, a set of 28 bacterial OTUs was found to be shared among all accessions. Functional analyses recovered evidence to support the predictions that changes in bacterial community compositions correspond to functional differentiation. Given the ease of cultivating this species, Asplenium delavayi is introduced here as a model organism to explore the ecological and evolutionary benefits created by mutualistic associations between bacteria and ferns.

The first complete chloroplast genome of Adiantum nelumboides (Pteridaceae), a rare and endangered fern species.

The complete chloroplast genome of a rare and endangered fern species Adiantum nelumboides was sequenced. The genome has a typical quadripartite structure with a length of 149,956 bp and 42.8% GC content. We annotated totally 131 genes, including 87 protein genes, 36 tRNA, and 8 rRNAs. This work provides crucial information for its phylogenetic and conservation of a critically endangered fern and its value as an ornamental and medicinal plant resource.